The operating principle of float-type carburetors is based on Bernoulli’s theorem which states that the energy per unit mass of a moving fluid is constant. As the air passes through the convergence of the Venturi duct, its velocity increases causing a drop in pressure and temperature. The pressure will drop proportionally to the mass airflow and is used to make fuel flow from the float chamber by placing a ‘U’-shaped jet into the Venturi. Engine suction creates a difference in air pressure at the throat of the Venturi duct and the air inlet resulting in a sucking effect. Besides the drop in pressure and temperature at the Venturi’s throat, the latter will increase again within the induction manifold as the throttle is opened.